Multiple cleanups

[Nuru]

what

• Partly revert Output instance endpoints, add attributes to random_pet that force a new instance #236 (see discussion below)
• Allow explicitly naming parameter group
• Use full name of engine for reserved DB instances
• Implement and close chore(deps): update terraform cloudposse/vpc/aws to v2.2.0 #197
• Implement and close chore(deps): update terraform cloudposse/route53-cluster-hostname/aws to v0.13.0 #199
• Implement and close Only set db_cluster_instance_class on the secondary cluster when local.is_serverless is false #230 Thank you @raymondchen625
• Implement and close feat: add option for local write forwarding #237 Thank you @Junaid-Tem
• Implement and close feat: reserved instances, allow reservation id for identifier  #239 Thank you @oycyc

why

• Closes 1.13.0 is forcing a recreate of the cluster instance  #241
• Closes Allow explicitly naming parameter group, so that Blue Green upgrades can be done across major versions #225
• Instance engine should match cluster engine
• Consolidate PRs

discussion: why partially revert #236?

PR #236 enhanced the random_pet that determines part of the name of the DB instances so that the name would change whenever the instances would need to be recreated. Unfortunately, as a side-effect, that causes all instances created with earlier versions of this module to be replaced.

Upon further investigation, it was determined that all the "keepers" added by the PR would also force the cluster to be replaced. Unlike replacing an instance, replacing the cluster results in data loss. Also, unless you change the name of the cluster, the module both before and after the PR would fail, because it would try to create a new cluster with the same name before destroying the old cluster.

We prefer this failure mode, requiring the user to explicitly destroy the cluster before creating the new one, because it puts the user on notice about the potential data loss. So given that the changes in the PR did not make something work that did not work before, and it did cause disruption, we reverted the change to the keepers.

[mergify]

Important

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[Nuru]

/terratest

[oycyc]

Appreciate this! Thanks for maintaining this module @Nuru 🙌

[korenyoni]

LGTM

[github-actions]

These changes were released in v1.15.0.